1/*
2 * Copyright 2006-2018 The OpenSSL Project Authors. All Rights Reserved.
3 *
4 * Licensed under the Apache License 2.0 (the "License"). You may not use
5 * this file except in compliance with the License. You can obtain a copy
6 * in the file LICENSE in the source distribution or at
7 * https://www.openssl.org/source/license.html
8 */
9
10#include <stdio.h>
11#include "internal/cryptlib.h"
12#include <openssl/x509.h>
13#include <openssl/ec.h>
14#include <openssl/bn.h>
15#include <openssl/cms.h>
16#include <openssl/asn1t.h>
17#include "crypto/asn1.h"
18#include "crypto/evp.h"
19#include "ec_local.h"
20
21#ifndef OPENSSL_NO_CMS
22static int ecdh_cms_decrypt(CMS_RecipientInfo *ri);
23static int ecdh_cms_encrypt(CMS_RecipientInfo *ri);
24#endif
25
26static int eckey_param2type(int *pptype, void **ppval, EC_KEY *ec_key)
27{
28 const EC_GROUP *group;
29 int nid;
30 if (ec_key == NULL || (group = EC_KEY_get0_group(ec_key)) == NULL) {
31 ECerr(EC_F_ECKEY_PARAM2TYPE, EC_R_MISSING_PARAMETERS);
32 return 0;
33 }
34 if (EC_GROUP_get_asn1_flag(group)
35 && (nid = EC_GROUP_get_curve_name(group)))
36 /* we have a 'named curve' => just set the OID */
37 {
38 *ppval = OBJ_nid2obj(nid);
39 *pptype = V_ASN1_OBJECT;
40 } else { /* explicit parameters */
41
42 ASN1_STRING *pstr = NULL;
43 pstr = ASN1_STRING_new();
44 if (pstr == NULL)
45 return 0;
46 pstr->length = i2d_ECParameters(ec_key, &pstr->data);
47 if (pstr->length <= 0) {
48 ASN1_STRING_free(pstr);
49 ECerr(EC_F_ECKEY_PARAM2TYPE, ERR_R_EC_LIB);
50 return 0;
51 }
52 *ppval = pstr;
53 *pptype = V_ASN1_SEQUENCE;
54 }
55 return 1;
56}
57
58static int eckey_pub_encode(X509_PUBKEY *pk, const EVP_PKEY *pkey)
59{
60 EC_KEY *ec_key = pkey->pkey.ec;
61 void *pval = NULL;
62 int ptype;
63 unsigned char *penc = NULL, *p;
64 int penclen;
65
66 if (!eckey_param2type(&ptype, &pval, ec_key)) {
67 ECerr(EC_F_ECKEY_PUB_ENCODE, ERR_R_EC_LIB);
68 return 0;
69 }
70 penclen = i2o_ECPublicKey(ec_key, NULL);
71 if (penclen <= 0)
72 goto err;
73 penc = OPENSSL_malloc(penclen);
74 if (penc == NULL)
75 goto err;
76 p = penc;
77 penclen = i2o_ECPublicKey(ec_key, &p);
78 if (penclen <= 0)
79 goto err;
80 if (X509_PUBKEY_set0_param(pk, OBJ_nid2obj(EVP_PKEY_EC),
81 ptype, pval, penc, penclen))
82 return 1;
83 err:
84 if (ptype == V_ASN1_OBJECT)
85 ASN1_OBJECT_free(pval);
86 else
87 ASN1_STRING_free(pval);
88 OPENSSL_free(penc);
89 return 0;
90}
91
92static EC_KEY *eckey_type2param(int ptype, const void *pval)
93{
94 EC_KEY *eckey = NULL;
95 EC_GROUP *group = NULL;
96
97 if (ptype == V_ASN1_SEQUENCE) {
98 const ASN1_STRING *pstr = pval;
99 const unsigned char *pm = pstr->data;
100 int pmlen = pstr->length;
101
102 if ((eckey = d2i_ECParameters(NULL, &pm, pmlen)) == NULL) {
103 ECerr(EC_F_ECKEY_TYPE2PARAM, EC_R_DECODE_ERROR);
104 goto ecerr;
105 }
106 } else if (ptype == V_ASN1_OBJECT) {
107 const ASN1_OBJECT *poid = pval;
108
109 /*
110 * type == V_ASN1_OBJECT => the parameters are given by an asn1 OID
111 */
112 if ((eckey = EC_KEY_new()) == NULL) {
113 ECerr(EC_F_ECKEY_TYPE2PARAM, ERR_R_MALLOC_FAILURE);
114 goto ecerr;
115 }
116 group = EC_GROUP_new_by_curve_name(OBJ_obj2nid(poid));
117 if (group == NULL)
118 goto ecerr;
119 EC_GROUP_set_asn1_flag(group, OPENSSL_EC_NAMED_CURVE);
120 if (EC_KEY_set_group(eckey, group) == 0)
121 goto ecerr;
122 EC_GROUP_free(group);
123 } else {
124 ECerr(EC_F_ECKEY_TYPE2PARAM, EC_R_DECODE_ERROR);
125 goto ecerr;
126 }
127
128 return eckey;
129
130 ecerr:
131 EC_KEY_free(eckey);
132 EC_GROUP_free(group);
133 return NULL;
134}
135
136static int eckey_pub_decode(EVP_PKEY *pkey, X509_PUBKEY *pubkey)
137{
138 const unsigned char *p = NULL;
139 const void *pval;
140 int ptype, pklen;
141 EC_KEY *eckey = NULL;
142 X509_ALGOR *palg;
143
144 if (!X509_PUBKEY_get0_param(NULL, &p, &pklen, &palg, pubkey))
145 return 0;
146 X509_ALGOR_get0(NULL, &ptype, &pval, palg);
147
148 eckey = eckey_type2param(ptype, pval);
149
150 if (!eckey) {
151 ECerr(EC_F_ECKEY_PUB_DECODE, ERR_R_EC_LIB);
152 return 0;
153 }
154
155 /* We have parameters now set public key */
156 if (!o2i_ECPublicKey(&eckey, &p, pklen)) {
157 ECerr(EC_F_ECKEY_PUB_DECODE, EC_R_DECODE_ERROR);
158 goto ecerr;
159 }
160
161 EVP_PKEY_assign_EC_KEY(pkey, eckey);
162 return 1;
163
164 ecerr:
165 EC_KEY_free(eckey);
166 return 0;
167}
168
169static int eckey_pub_cmp(const EVP_PKEY *a, const EVP_PKEY *b)
170{
171 int r;
172 const EC_GROUP *group = EC_KEY_get0_group(b->pkey.ec);
173 const EC_POINT *pa = EC_KEY_get0_public_key(a->pkey.ec),
174 *pb = EC_KEY_get0_public_key(b->pkey.ec);
175 if (group == NULL || pa == NULL || pb == NULL)
176 return -2;
177 r = EC_POINT_cmp(group, pa, pb, NULL);
178 if (r == 0)
179 return 1;
180 if (r == 1)
181 return 0;
182 return -2;
183}
184
185static int eckey_priv_decode(EVP_PKEY *pkey, const PKCS8_PRIV_KEY_INFO *p8)
186{
187 const unsigned char *p = NULL;
188 const void *pval;
189 int ptype, pklen;
190 EC_KEY *eckey = NULL;
191 const X509_ALGOR *palg;
192
193 if (!PKCS8_pkey_get0(NULL, &p, &pklen, &palg, p8))
194 return 0;
195 X509_ALGOR_get0(NULL, &ptype, &pval, palg);
196
197 eckey = eckey_type2param(ptype, pval);
198
199 if (eckey == NULL)
200 goto ecliberr;
201
202 /* We have parameters now set private key */
203 if (!d2i_ECPrivateKey(&eckey, &p, pklen)) {
204 ECerr(EC_F_ECKEY_PRIV_DECODE, EC_R_DECODE_ERROR);
205 goto ecerr;
206 }
207
208 EVP_PKEY_assign_EC_KEY(pkey, eckey);
209 return 1;
210
211 ecliberr:
212 ECerr(EC_F_ECKEY_PRIV_DECODE, ERR_R_EC_LIB);
213 ecerr:
214 EC_KEY_free(eckey);
215 return 0;
216}
217
218static int eckey_priv_encode(PKCS8_PRIV_KEY_INFO *p8, const EVP_PKEY *pkey)
219{
220 EC_KEY ec_key = *(pkey->pkey.ec);
221 unsigned char *ep, *p;
222 int eplen, ptype;
223 void *pval;
224 unsigned int old_flags;
225
226 if (!eckey_param2type(&ptype, &pval, &ec_key)) {
227 ECerr(EC_F_ECKEY_PRIV_ENCODE, EC_R_DECODE_ERROR);
228 return 0;
229 }
230
231 /* set the private key */
232
233 /*
234 * do not include the parameters in the SEC1 private key see PKCS#11
235 * 12.11
236 */
237 old_flags = EC_KEY_get_enc_flags(&ec_key);
238 EC_KEY_set_enc_flags(&ec_key, old_flags | EC_PKEY_NO_PARAMETERS);
239
240 eplen = i2d_ECPrivateKey(&ec_key, NULL);
241 if (!eplen) {
242 ECerr(EC_F_ECKEY_PRIV_ENCODE, ERR_R_EC_LIB);
243 return 0;
244 }
245 ep = OPENSSL_malloc(eplen);
246 if (ep == NULL) {
247 ECerr(EC_F_ECKEY_PRIV_ENCODE, ERR_R_MALLOC_FAILURE);
248 return 0;
249 }
250 p = ep;
251 if (!i2d_ECPrivateKey(&ec_key, &p)) {
252 OPENSSL_free(ep);
253 ECerr(EC_F_ECKEY_PRIV_ENCODE, ERR_R_EC_LIB);
254 return 0;
255 }
256
257 if (!PKCS8_pkey_set0(p8, OBJ_nid2obj(NID_X9_62_id_ecPublicKey), 0,
258 ptype, pval, ep, eplen)) {
259 OPENSSL_free(ep);
260 return 0;
261 }
262
263 return 1;
264}
265
266static int int_ec_size(const EVP_PKEY *pkey)
267{
268 return ECDSA_size(pkey->pkey.ec);
269}
270
271static int ec_bits(const EVP_PKEY *pkey)
272{
273 return EC_GROUP_order_bits(EC_KEY_get0_group(pkey->pkey.ec));
274}
275
276static int ec_security_bits(const EVP_PKEY *pkey)
277{
278 int ecbits = ec_bits(pkey);
279 if (ecbits >= 512)
280 return 256;
281 if (ecbits >= 384)
282 return 192;
283 if (ecbits >= 256)
284 return 128;
285 if (ecbits >= 224)
286 return 112;
287 if (ecbits >= 160)
288 return 80;
289 return ecbits / 2;
290}
291
292static int ec_missing_parameters(const EVP_PKEY *pkey)
293{
294 if (pkey->pkey.ec == NULL || EC_KEY_get0_group(pkey->pkey.ec) == NULL)
295 return 1;
296 return 0;
297}
298
299static int ec_copy_parameters(EVP_PKEY *to, const EVP_PKEY *from)
300{
301 EC_GROUP *group = EC_GROUP_dup(EC_KEY_get0_group(from->pkey.ec));
302
303 if (group == NULL)
304 return 0;
305 if (to->pkey.ec == NULL) {
306 to->pkey.ec = EC_KEY_new();
307 if (to->pkey.ec == NULL)
308 goto err;
309 }
310 if (EC_KEY_set_group(to->pkey.ec, group) == 0)
311 goto err;
312 EC_GROUP_free(group);
313 return 1;
314 err:
315 EC_GROUP_free(group);
316 return 0;
317}
318
319static int ec_cmp_parameters(const EVP_PKEY *a, const EVP_PKEY *b)
320{
321 const EC_GROUP *group_a = EC_KEY_get0_group(a->pkey.ec),
322 *group_b = EC_KEY_get0_group(b->pkey.ec);
323 if (group_a == NULL || group_b == NULL)
324 return -2;
325 if (EC_GROUP_cmp(group_a, group_b, NULL))
326 return 0;
327 else
328 return 1;
329}
330
331static void int_ec_free(EVP_PKEY *pkey)
332{
333 EC_KEY_free(pkey->pkey.ec);
334}
335
336typedef enum {
337 EC_KEY_PRINT_PRIVATE,
338 EC_KEY_PRINT_PUBLIC,
339 EC_KEY_PRINT_PARAM
340} ec_print_t;
341
342static int do_EC_KEY_print(BIO *bp, const EC_KEY *x, int off, ec_print_t ktype)
343{
344 const char *ecstr;
345 unsigned char *priv = NULL, *pub = NULL;
346 size_t privlen = 0, publen = 0;
347 int ret = 0;
348 const EC_GROUP *group;
349
350 if (x == NULL || (group = EC_KEY_get0_group(x)) == NULL) {
351 ECerr(EC_F_DO_EC_KEY_PRINT, ERR_R_PASSED_NULL_PARAMETER);
352 return 0;
353 }
354
355 if (ktype != EC_KEY_PRINT_PARAM && EC_KEY_get0_public_key(x) != NULL) {
356 publen = EC_KEY_key2buf(x, EC_KEY_get_conv_form(x), &pub, NULL);
357 if (publen == 0)
358 goto err;
359 }
360
361 if (ktype == EC_KEY_PRINT_PRIVATE && EC_KEY_get0_private_key(x) != NULL) {
362 privlen = EC_KEY_priv2buf(x, &priv);
363 if (privlen == 0)
364 goto err;
365 }
366
367 if (ktype == EC_KEY_PRINT_PRIVATE)
368 ecstr = "Private-Key";
369 else if (ktype == EC_KEY_PRINT_PUBLIC)
370 ecstr = "Public-Key";
371 else
372 ecstr = "ECDSA-Parameters";
373
374 if (!BIO_indent(bp, off, 128))
375 goto err;
376 if (BIO_printf(bp, "%s: (%d bit)\n", ecstr,
377 EC_GROUP_order_bits(group)) <= 0)
378 goto err;
379
380 if (privlen != 0) {
381 if (BIO_printf(bp, "%*spriv:\n", off, "") <= 0)
382 goto err;
383 if (ASN1_buf_print(bp, priv, privlen, off + 4) == 0)
384 goto err;
385 }
386
387 if (publen != 0) {
388 if (BIO_printf(bp, "%*spub:\n", off, "") <= 0)
389 goto err;
390 if (ASN1_buf_print(bp, pub, publen, off + 4) == 0)
391 goto err;
392 }
393
394 if (!ECPKParameters_print(bp, group, off))
395 goto err;
396 ret = 1;
397 err:
398 if (!ret)
399 ECerr(EC_F_DO_EC_KEY_PRINT, ERR_R_EC_LIB);
400 OPENSSL_clear_free(priv, privlen);
401 OPENSSL_free(pub);
402 return ret;
403}
404
405static int eckey_param_decode(EVP_PKEY *pkey,
406 const unsigned char **pder, int derlen)
407{
408 EC_KEY *eckey;
409
410 if ((eckey = d2i_ECParameters(NULL, pder, derlen)) == NULL) {
411 ECerr(EC_F_ECKEY_PARAM_DECODE, ERR_R_EC_LIB);
412 return 0;
413 }
414 EVP_PKEY_assign_EC_KEY(pkey, eckey);
415 return 1;
416}
417
418static int eckey_param_encode(const EVP_PKEY *pkey, unsigned char **pder)
419{
420 return i2d_ECParameters(pkey->pkey.ec, pder);
421}
422
423static int eckey_param_print(BIO *bp, const EVP_PKEY *pkey, int indent,
424 ASN1_PCTX *ctx)
425{
426 return do_EC_KEY_print(bp, pkey->pkey.ec, indent, EC_KEY_PRINT_PARAM);
427}
428
429static int eckey_pub_print(BIO *bp, const EVP_PKEY *pkey, int indent,
430 ASN1_PCTX *ctx)
431{
432 return do_EC_KEY_print(bp, pkey->pkey.ec, indent, EC_KEY_PRINT_PUBLIC);
433}
434
435static int eckey_priv_print(BIO *bp, const EVP_PKEY *pkey, int indent,
436 ASN1_PCTX *ctx)
437{
438 return do_EC_KEY_print(bp, pkey->pkey.ec, indent, EC_KEY_PRINT_PRIVATE);
439}
440
441static int old_ec_priv_decode(EVP_PKEY *pkey,
442 const unsigned char **pder, int derlen)
443{
444 EC_KEY *ec;
445
446 if ((ec = d2i_ECPrivateKey(NULL, pder, derlen)) == NULL) {
447 ECerr(EC_F_OLD_EC_PRIV_DECODE, EC_R_DECODE_ERROR);
448 return 0;
449 }
450 EVP_PKEY_assign_EC_KEY(pkey, ec);
451 return 1;
452}
453
454static int old_ec_priv_encode(const EVP_PKEY *pkey, unsigned char **pder)
455{
456 return i2d_ECPrivateKey(pkey->pkey.ec, pder);
457}
458
459static int ec_pkey_ctrl(EVP_PKEY *pkey, int op, long arg1, void *arg2)
460{
461 switch (op) {
462 case ASN1_PKEY_CTRL_PKCS7_SIGN:
463 if (arg1 == 0) {
464 int snid, hnid;
465 X509_ALGOR *alg1, *alg2;
466 PKCS7_SIGNER_INFO_get0_algs(arg2, NULL, &alg1, &alg2);
467 if (alg1 == NULL || alg1->algorithm == NULL)
468 return -1;
469 hnid = OBJ_obj2nid(alg1->algorithm);
470 if (hnid == NID_undef)
471 return -1;
472 if (!OBJ_find_sigid_by_algs(&snid, hnid, EVP_PKEY_id(pkey)))
473 return -1;
474 X509_ALGOR_set0(alg2, OBJ_nid2obj(snid), V_ASN1_UNDEF, 0);
475 }
476 return 1;
477#ifndef OPENSSL_NO_CMS
478 case ASN1_PKEY_CTRL_CMS_SIGN:
479 if (arg1 == 0) {
480 int snid, hnid;
481 X509_ALGOR *alg1, *alg2;
482 CMS_SignerInfo_get0_algs(arg2, NULL, NULL, &alg1, &alg2);
483 if (alg1 == NULL || alg1->algorithm == NULL)
484 return -1;
485 hnid = OBJ_obj2nid(alg1->algorithm);
486 if (hnid == NID_undef)
487 return -1;
488 if (!OBJ_find_sigid_by_algs(&snid, hnid, EVP_PKEY_id(pkey)))
489 return -1;
490 X509_ALGOR_set0(alg2, OBJ_nid2obj(snid), V_ASN1_UNDEF, 0);
491 }
492 return 1;
493
494 case ASN1_PKEY_CTRL_CMS_ENVELOPE:
495 if (arg1 == 1)
496 return ecdh_cms_decrypt(arg2);
497 else if (arg1 == 0)
498 return ecdh_cms_encrypt(arg2);
499 return -2;
500
501 case ASN1_PKEY_CTRL_CMS_RI_TYPE:
502 *(int *)arg2 = CMS_RECIPINFO_AGREE;
503 return 1;
504#endif
505
506 case ASN1_PKEY_CTRL_DEFAULT_MD_NID:
507 if (EVP_PKEY_id(pkey) == EVP_PKEY_SM2) {
508 /* For SM2, the only valid digest-alg is SM3 */
509 *(int *)arg2 = NID_sm3;
510 } else {
511 *(int *)arg2 = NID_sha256;
512 }
513 return 1;
514
515 case ASN1_PKEY_CTRL_SET1_TLS_ENCPT:
516 return EC_KEY_oct2key(EVP_PKEY_get0_EC_KEY(pkey), arg2, arg1, NULL);
517
518 case ASN1_PKEY_CTRL_GET1_TLS_ENCPT:
519 return EC_KEY_key2buf(EVP_PKEY_get0_EC_KEY(pkey),
520 POINT_CONVERSION_UNCOMPRESSED, arg2, NULL);
521
522 default:
523 return -2;
524
525 }
526
527}
528
529static int ec_pkey_check(const EVP_PKEY *pkey)
530{
531 EC_KEY *eckey = pkey->pkey.ec;
532
533 /* stay consistent to what EVP_PKEY_check demands */
534 if (eckey->priv_key == NULL) {
535 ECerr(EC_F_EC_PKEY_CHECK, EC_R_MISSING_PRIVATE_KEY);
536 return 0;
537 }
538
539 return EC_KEY_check_key(eckey);
540}
541
542static int ec_pkey_public_check(const EVP_PKEY *pkey)
543{
544 EC_KEY *eckey = pkey->pkey.ec;
545
546 /*
547 * Note: it unnecessary to check eckey->pub_key here since
548 * it will be checked in EC_KEY_check_key(). In fact, the
549 * EC_KEY_check_key() mainly checks the public key, and checks
550 * the private key optionally (only if there is one). So if
551 * someone passes a whole EC key (public + private), this
552 * will also work...
553 */
554
555 return EC_KEY_check_key(eckey);
556}
557
558static int ec_pkey_param_check(const EVP_PKEY *pkey)
559{
560 EC_KEY *eckey = pkey->pkey.ec;
561
562 /* stay consistent to what EVP_PKEY_check demands */
563 if (eckey->group == NULL) {
564 ECerr(EC_F_EC_PKEY_PARAM_CHECK, EC_R_MISSING_PARAMETERS);
565 return 0;
566 }
567
568 return EC_GROUP_check(eckey->group, NULL);
569}
570
571const EVP_PKEY_ASN1_METHOD eckey_asn1_meth = {
572 EVP_PKEY_EC,
573 EVP_PKEY_EC,
574 0,
575 "EC",
576 "OpenSSL EC algorithm",
577
578 eckey_pub_decode,
579 eckey_pub_encode,
580 eckey_pub_cmp,
581 eckey_pub_print,
582
583 eckey_priv_decode,
584 eckey_priv_encode,
585 eckey_priv_print,
586
587 int_ec_size,
588 ec_bits,
589 ec_security_bits,
590
591 eckey_param_decode,
592 eckey_param_encode,
593 ec_missing_parameters,
594 ec_copy_parameters,
595 ec_cmp_parameters,
596 eckey_param_print,
597 0,
598
599 int_ec_free,
600 ec_pkey_ctrl,
601 old_ec_priv_decode,
602 old_ec_priv_encode,
603
604 0, 0, 0,
605
606 ec_pkey_check,
607 ec_pkey_public_check,
608 ec_pkey_param_check
609};
610
611#if !defined(OPENSSL_NO_SM2)
612const EVP_PKEY_ASN1_METHOD sm2_asn1_meth = {
613 EVP_PKEY_SM2,
614 EVP_PKEY_EC,
615 ASN1_PKEY_ALIAS
616};
617#endif
618
619int EC_KEY_print(BIO *bp, const EC_KEY *x, int off)
620{
621 int private = EC_KEY_get0_private_key(x) != NULL;
622
623 return do_EC_KEY_print(bp, x, off,
624 private ? EC_KEY_PRINT_PRIVATE : EC_KEY_PRINT_PUBLIC);
625}
626
627int ECParameters_print(BIO *bp, const EC_KEY *x)
628{
629 return do_EC_KEY_print(bp, x, 4, EC_KEY_PRINT_PARAM);
630}
631
632#ifndef OPENSSL_NO_CMS
633
634static int ecdh_cms_set_peerkey(EVP_PKEY_CTX *pctx,
635 X509_ALGOR *alg, ASN1_BIT_STRING *pubkey)
636{
637 const ASN1_OBJECT *aoid;
638 int atype;
639 const void *aval;
640 int rv = 0;
641 EVP_PKEY *pkpeer = NULL;
642 EC_KEY *ecpeer = NULL;
643 const unsigned char *p;
644 int plen;
645 X509_ALGOR_get0(&aoid, &atype, &aval, alg);
646 if (OBJ_obj2nid(aoid) != NID_X9_62_id_ecPublicKey)
647 goto err;
648 /* If absent parameters get group from main key */
649 if (atype == V_ASN1_UNDEF || atype == V_ASN1_NULL) {
650 const EC_GROUP *grp;
651 EVP_PKEY *pk;
652 pk = EVP_PKEY_CTX_get0_pkey(pctx);
653 if (pk == NULL)
654 goto err;
655 grp = EC_KEY_get0_group(pk->pkey.ec);
656 ecpeer = EC_KEY_new();
657 if (ecpeer == NULL)
658 goto err;
659 if (!EC_KEY_set_group(ecpeer, grp))
660 goto err;
661 } else {
662 ecpeer = eckey_type2param(atype, aval);
663 if (!ecpeer)
664 goto err;
665 }
666 /* We have parameters now set public key */
667 plen = ASN1_STRING_length(pubkey);
668 p = ASN1_STRING_get0_data(pubkey);
669 if (p == NULL || plen == 0)
670 goto err;
671 if (!o2i_ECPublicKey(&ecpeer, &p, plen))
672 goto err;
673 pkpeer = EVP_PKEY_new();
674 if (pkpeer == NULL)
675 goto err;
676 EVP_PKEY_set1_EC_KEY(pkpeer, ecpeer);
677 if (EVP_PKEY_derive_set_peer(pctx, pkpeer) > 0)
678 rv = 1;
679 err:
680 EC_KEY_free(ecpeer);
681 EVP_PKEY_free(pkpeer);
682 return rv;
683}
684
685/* Set KDF parameters based on KDF NID */
686static int ecdh_cms_set_kdf_param(EVP_PKEY_CTX *pctx, int eckdf_nid)
687{
688 int kdf_nid, kdfmd_nid, cofactor;
689 const EVP_MD *kdf_md;
690 if (eckdf_nid == NID_undef)
691 return 0;
692
693 /* Lookup KDF type, cofactor mode and digest */
694 if (!OBJ_find_sigid_algs(eckdf_nid, &kdfmd_nid, &kdf_nid))
695 return 0;
696
697 if (kdf_nid == NID_dh_std_kdf)
698 cofactor = 0;
699 else if (kdf_nid == NID_dh_cofactor_kdf)
700 cofactor = 1;
701 else
702 return 0;
703
704 if (EVP_PKEY_CTX_set_ecdh_cofactor_mode(pctx, cofactor) <= 0)
705 return 0;
706
707 if (EVP_PKEY_CTX_set_ecdh_kdf_type(pctx, EVP_PKEY_ECDH_KDF_X9_63) <= 0)
708 return 0;
709
710 kdf_md = EVP_get_digestbynid(kdfmd_nid);
711 if (!kdf_md)
712 return 0;
713
714 if (EVP_PKEY_CTX_set_ecdh_kdf_md(pctx, kdf_md) <= 0)
715 return 0;
716 return 1;
717}
718
719static int ecdh_cms_set_shared_info(EVP_PKEY_CTX *pctx, CMS_RecipientInfo *ri)
720{
721 int rv = 0;
722
723 X509_ALGOR *alg, *kekalg = NULL;
724 ASN1_OCTET_STRING *ukm;
725 const unsigned char *p;
726 unsigned char *der = NULL;
727 int plen, keylen;
728 const EVP_CIPHER *kekcipher;
729 EVP_CIPHER_CTX *kekctx;
730
731 if (!CMS_RecipientInfo_kari_get0_alg(ri, &alg, &ukm))
732 return 0;
733
734 if (!ecdh_cms_set_kdf_param(pctx, OBJ_obj2nid(alg->algorithm))) {
735 ECerr(EC_F_ECDH_CMS_SET_SHARED_INFO, EC_R_KDF_PARAMETER_ERROR);
736 return 0;
737 }
738
739 if (alg->parameter->type != V_ASN1_SEQUENCE)
740 return 0;
741
742 p = alg->parameter->value.sequence->data;
743 plen = alg->parameter->value.sequence->length;
744 kekalg = d2i_X509_ALGOR(NULL, &p, plen);
745 if (!kekalg)
746 goto err;
747 kekctx = CMS_RecipientInfo_kari_get0_ctx(ri);
748 if (!kekctx)
749 goto err;
750 kekcipher = EVP_get_cipherbyobj(kekalg->algorithm);
751 if (!kekcipher || EVP_CIPHER_mode(kekcipher) != EVP_CIPH_WRAP_MODE)
752 goto err;
753 if (!EVP_EncryptInit_ex(kekctx, kekcipher, NULL, NULL, NULL))
754 goto err;
755 if (EVP_CIPHER_asn1_to_param(kekctx, kekalg->parameter) <= 0)
756 goto err;
757
758 keylen = EVP_CIPHER_CTX_key_length(kekctx);
759 if (EVP_PKEY_CTX_set_ecdh_kdf_outlen(pctx, keylen) <= 0)
760 goto err;
761
762 plen = CMS_SharedInfo_encode(&der, kekalg, ukm, keylen);
763
764 if (!plen)
765 goto err;
766
767 if (EVP_PKEY_CTX_set0_ecdh_kdf_ukm(pctx, der, plen) <= 0)
768 goto err;
769 der = NULL;
770
771 rv = 1;
772 err:
773 X509_ALGOR_free(kekalg);
774 OPENSSL_free(der);
775 return rv;
776}
777
778static int ecdh_cms_decrypt(CMS_RecipientInfo *ri)
779{
780 EVP_PKEY_CTX *pctx;
781 pctx = CMS_RecipientInfo_get0_pkey_ctx(ri);
782 if (!pctx)
783 return 0;
784 /* See if we need to set peer key */
785 if (!EVP_PKEY_CTX_get0_peerkey(pctx)) {
786 X509_ALGOR *alg;
787 ASN1_BIT_STRING *pubkey;
788 if (!CMS_RecipientInfo_kari_get0_orig_id(ri, &alg, &pubkey,
789 NULL, NULL, NULL))
790 return 0;
791 if (!alg || !pubkey)
792 return 0;
793 if (!ecdh_cms_set_peerkey(pctx, alg, pubkey)) {
794 ECerr(EC_F_ECDH_CMS_DECRYPT, EC_R_PEER_KEY_ERROR);
795 return 0;
796 }
797 }
798 /* Set ECDH derivation parameters and initialise unwrap context */
799 if (!ecdh_cms_set_shared_info(pctx, ri)) {
800 ECerr(EC_F_ECDH_CMS_DECRYPT, EC_R_SHARED_INFO_ERROR);
801 return 0;
802 }
803 return 1;
804}
805
806static int ecdh_cms_encrypt(CMS_RecipientInfo *ri)
807{
808 EVP_PKEY_CTX *pctx;
809 EVP_PKEY *pkey;
810 EVP_CIPHER_CTX *ctx;
811 int keylen;
812 X509_ALGOR *talg, *wrap_alg = NULL;
813 const ASN1_OBJECT *aoid;
814 ASN1_BIT_STRING *pubkey;
815 ASN1_STRING *wrap_str;
816 ASN1_OCTET_STRING *ukm;
817 unsigned char *penc = NULL;
818 int penclen;
819 int rv = 0;
820 int ecdh_nid, kdf_type, kdf_nid, wrap_nid;
821 const EVP_MD *kdf_md;
822 pctx = CMS_RecipientInfo_get0_pkey_ctx(ri);
823 if (!pctx)
824 return 0;
825 /* Get ephemeral key */
826 pkey = EVP_PKEY_CTX_get0_pkey(pctx);
827 if (!CMS_RecipientInfo_kari_get0_orig_id(ri, &talg, &pubkey,
828 NULL, NULL, NULL))
829 goto err;
830 X509_ALGOR_get0(&aoid, NULL, NULL, talg);
831 /* Is everything uninitialised? */
832 if (aoid == OBJ_nid2obj(NID_undef)) {
833
834 EC_KEY *eckey = pkey->pkey.ec;
835 /* Set the key */
836 unsigned char *p;
837
838 penclen = i2o_ECPublicKey(eckey, NULL);
839 if (penclen <= 0)
840 goto err;
841 penc = OPENSSL_malloc(penclen);
842 if (penc == NULL)
843 goto err;
844 p = penc;
845 penclen = i2o_ECPublicKey(eckey, &p);
846 if (penclen <= 0)
847 goto err;
848 ASN1_STRING_set0(pubkey, penc, penclen);
849 pubkey->flags &= ~(ASN1_STRING_FLAG_BITS_LEFT | 0x07);
850 pubkey->flags |= ASN1_STRING_FLAG_BITS_LEFT;
851
852 penc = NULL;
853 X509_ALGOR_set0(talg, OBJ_nid2obj(NID_X9_62_id_ecPublicKey),
854 V_ASN1_UNDEF, NULL);
855 }
856
857 /* See if custom parameters set */
858 kdf_type = EVP_PKEY_CTX_get_ecdh_kdf_type(pctx);
859 if (kdf_type <= 0)
860 goto err;
861 if (!EVP_PKEY_CTX_get_ecdh_kdf_md(pctx, &kdf_md))
862 goto err;
863 ecdh_nid = EVP_PKEY_CTX_get_ecdh_cofactor_mode(pctx);
864 if (ecdh_nid < 0)
865 goto err;
866 else if (ecdh_nid == 0)
867 ecdh_nid = NID_dh_std_kdf;
868 else if (ecdh_nid == 1)
869 ecdh_nid = NID_dh_cofactor_kdf;
870
871 if (kdf_type == EVP_PKEY_ECDH_KDF_NONE) {
872 kdf_type = EVP_PKEY_ECDH_KDF_X9_63;
873 if (EVP_PKEY_CTX_set_ecdh_kdf_type(pctx, kdf_type) <= 0)
874 goto err;
875 } else
876 /* Unknown KDF */
877 goto err;
878 if (kdf_md == NULL) {
879 /* Fixme later for better MD */
880 kdf_md = EVP_sha1();
881 if (EVP_PKEY_CTX_set_ecdh_kdf_md(pctx, kdf_md) <= 0)
882 goto err;
883 }
884
885 if (!CMS_RecipientInfo_kari_get0_alg(ri, &talg, &ukm))
886 goto err;
887
888 /* Lookup NID for KDF+cofactor+digest */
889
890 if (!OBJ_find_sigid_by_algs(&kdf_nid, EVP_MD_type(kdf_md), ecdh_nid))
891 goto err;
892 /* Get wrap NID */
893 ctx = CMS_RecipientInfo_kari_get0_ctx(ri);
894 wrap_nid = EVP_CIPHER_CTX_type(ctx);
895 keylen = EVP_CIPHER_CTX_key_length(ctx);
896
897 /* Package wrap algorithm in an AlgorithmIdentifier */
898
899 wrap_alg = X509_ALGOR_new();
900 if (wrap_alg == NULL)
901 goto err;
902 wrap_alg->algorithm = OBJ_nid2obj(wrap_nid);
903 wrap_alg->parameter = ASN1_TYPE_new();
904 if (wrap_alg->parameter == NULL)
905 goto err;
906 if (EVP_CIPHER_param_to_asn1(ctx, wrap_alg->parameter) <= 0)
907 goto err;
908 if (ASN1_TYPE_get(wrap_alg->parameter) == NID_undef) {
909 ASN1_TYPE_free(wrap_alg->parameter);
910 wrap_alg->parameter = NULL;
911 }
912
913 if (EVP_PKEY_CTX_set_ecdh_kdf_outlen(pctx, keylen) <= 0)
914 goto err;
915
916 penclen = CMS_SharedInfo_encode(&penc, wrap_alg, ukm, keylen);
917
918 if (!penclen)
919 goto err;
920
921 if (EVP_PKEY_CTX_set0_ecdh_kdf_ukm(pctx, penc, penclen) <= 0)
922 goto err;
923 penc = NULL;
924
925 /*
926 * Now need to wrap encoding of wrap AlgorithmIdentifier into parameter
927 * of another AlgorithmIdentifier.
928 */
929 penclen = i2d_X509_ALGOR(wrap_alg, &penc);
930 if (!penc || !penclen)
931 goto err;
932 wrap_str = ASN1_STRING_new();
933 if (wrap_str == NULL)
934 goto err;
935 ASN1_STRING_set0(wrap_str, penc, penclen);
936 penc = NULL;
937 X509_ALGOR_set0(talg, OBJ_nid2obj(kdf_nid), V_ASN1_SEQUENCE, wrap_str);
938
939 rv = 1;
940
941 err:
942 OPENSSL_free(penc);
943 X509_ALGOR_free(wrap_alg);
944 return rv;
945}
946
947#endif
948